Directly under your Google+ profile picture is information about the people you have in your circles and the circles you are included in. Much like everything else on your profile page, this, too, you can edit.
From your Google+ profile page, click the "Edit profile" button, then hover over your Circles information. To edit it, click the gray globe icon. From here, you can choose whether or not you want others to see who you have in your Circles and who has put you in their Circle.